Noob ABS Question

[DaBeef]

I tried searching and could find no answer, so I will be properly chastised if it's been covered before, but here goes. I have a new to me R1150RT with ABS. I have never had a bike with ABS before, nor one where the brakes felt as powerful to me. There is one exception, however. When braking briskly, (usually on a downward slope) if the front end comes in contact with a bump, (for example a break in the pavement or "tar snake") the front brake releases for a second. The action is enough to throw my weight back as though in acceleration. The brake always reapplies quickly enough that I stop short of where I would have thought, but is a little disconcerting. The phenomenon seems worst when there is engine braking present. Is this the ABS or is my teutonic noobness just aggravating some drive line issues?

[waylap]

I have an 04 and have never experienced this on mine...but what you are describing is EXACTLY what happened to me constantly on a police electra glide with first production ABS. As I would come to a red light, engine braking and light pressure on brakes, they would suddenly "let go" feeling like a sudden lurch forward then reaply. Strange to hear about this on an RT, I would think something is starting to need service if this is happening. This problem I described on the electra glide would go away with the clutch pulled in.

[Boffin]

That is what is known as the "Ice patch effect". What happens is that when the rear hits the bump/ripple, it kicks off the ground and locks, so the ABS releases the rear brake. If the rear does not spin up in a short time, the brakes go into anti-stoppie mode and releases the front brake to get the rear down again. This effect is lessened if both brake levers (front and rear) are used and exagerated if only the front brake lever used.

 

Andy

[waylap]

Now that I've thought about this more, it was when rolling to a stop using only rear brake for that last 30 feet or so and it was in gear, clutch engaged....felt like hitting ice. But then again this was an H-D.

[jwg122843]

I have experienced this on my R1150RT and the time I first noticed it was a pavement transition where the tires momentarily loose contact with the roadway. A little of an annoyance but I do love the ABS brakes.

[DaBeef]

Tanks for the replies, I thought that might be it. I will work on using both pedal and lever and keeping the clutch in. The brakes work so well that I keep over estimating my stopping distance but hey, that's a great problem to have

[outpost22]

Tanks for the replies, I thought that might be it. I will work on using both pedal and lever and keeping the clutch in. The brakes work so well that I keep over estimating my stopping distance but hey, that's a great problem to have

 

What, praytell may I ask, type of bike(s) did you own before that had such mediocre brakes?

[waylap]

Hey, I remember my first ride on an 03 1150RT! I nearly launched off the front of the bike when I came up to my first red light. I was thinking WOW, now those are some brakes! The power assisted linked ABS can be a real experience, especially going from an H-D!

[AndyS]

... When braking briskly, (usually on a downward slope) if the front end comes in contact with a bump, (for example a break in the pavement or "tar snake") the front brake releases for a second. The action is enough to throw my weight back as though in acceleration.....

I had a BMW addendum sent to me about this (which I have now lost).

As Andy said, some call it Ice patch effect' I think I had it referred to as 'Surfing'. What you experience (under the wrong conditions) is nothing short of terriying. However apparently they all do that!

Andy

[ElevenFifty]

Happened to me once on a rumble strip approaching a rural 4 way stop ... I've tried to recreate the ABS release every since (in safe conditions) with no luck.

[DaBeef]

What, praytell may I ask, type of bike(s) did you own before that had such mediocre brakes?

 

Well, the last one was a Triumph Thruxton, not exactly a paragon of modern design The 599 I had before may have been more powerful, but I had just come off of MX bikes so I was still getting used to pavement stops. All in all I am adjusting my mental stopping reference. These seem like they require soooo much less lever pressure.

[T__]

I tried searching and could find no answer, so I will be properly chastised if it's been covered before, but here goes. I have a new to me R1150RT with ABS. I have never had a bike with ABS before, nor one where the brakes felt as powerful to me. There is one exception, however. When braking briskly, (usually on a downward slope) if the front end comes in contact with a bump, (for example a break in the pavement or "tar snake") the front brake releases for a second. The action is enough to throw my weight back as though in acceleration. The brake always reapplies quickly enough that I stop short of where I would have thought, but is a little disconcerting. The phenomenon seems worst when there is engine braking present. Is this the ABS or is my teutonic noobness just aggravating some drive line issues?

 

 

 

DaBeef, as mentioned they all do that to some extent but the early 2002 seemed to do that the most often & with the abruptest release & jump..

 

There was a new release ABS controller for the later 02 RT’s with a different algorithm & braking slope to eliminate that somewhat.. My guess is you have an early 02 RT & the original owner never complained to the dealer so the controller never got updated (BTW they won’t do it for you now if it wasn’t done originally under warrantee)

 

The early 02 RT’s were real bad for releasing the front brake if the rear wheel skipped over an expansion joint or rock while briskly stopping..

 

What I found helped my 02 RT a lot was replacing the rear brake pads with the earlier R1000R rear pads as those were organic so had a less aggressive friction material & lessened the rear brake lock up problem. Didn’t eliminate it but did help.. They do wear faster though..

 

Twisty

 

[DaBeef]

Thanks Twisty, I will add that to my list of possible solutions. It very well could be that I am a lot more ham fisted than the previous owner and I think, looking at the service log that it might be due some pads.